Un Paseo Fotográfico Por La Vida De Sophus

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Un Paseo Fotográfico Por La Vida De Sophus Lecturas Matem´aticas Volumen 31 (2010), p´aginas 55–75 ISSN 0120–1980 Un paseo fotogr´aficoporlavidadeSophusLie Juan Nu´nez,˜ Alicia Prieto & Vanesa Sanchez–Canales´ Universidad de Sevilla, Sevilla, Espa˜na Abstract. It is quite a lot scarce the literature on the Norwegian mathematician Sophus Lie, in spite of being him, as the great vol- ume of his works demonstrates, one of the most important mathemati- cians throughout the history. In this paper, some of the non well-known photographs related with his life are shown. A particular review of the people and circumstances appearing in each of them is described. Key words and phrases. Sophus Lie; biography, fotography. 2000 AMS Mathematics Subject Classification. 01A55, 01A70 Resumen. No es muy numerosa la documentaci´on escrita existente sobre el matem´atico noruego Sophus Lie,apesardeser´este, por el volumen de sus obras, uno de los m´as importantes matem´aticos de todos los tiempos. En este art´ıculo se muestran algunas de las escasa- mente conocidas fotograf´ıas relacionadas con la vida de Sophus Lie, realiz´andose un detallado estudio de cada una de ellas, con especial menci´on de los personajes que aparecen y de las circunstancias que cada una de ellas refleja. Introducci´on En honor a la verdad, no puede decirse que Sophus Lie sea un matem´atico muy conocido, no ya por la sociedad en general, sino ni siquiera por la comu- nidad cient´ıfica en particular. Lejos este conocimiento del que se tiene de otros matem´aticos, como Euler o Gauss, por ejemplo. Y esto, a pesar de que la obra cient´ıfica de Lie es particularmente extensa y de que tanto sus descubri- mientos como fundamentalmente las aplicaciones de los mismos han marcado un hito en el campo de otras disciplinas, como la f´ısica y las ingenier´ıas, por ejemplo. No en vano fue el propio Albert Einstein el que afirmase que: “sin 56 J. Nu´nez,˜ A. Prieto & V. Sanchez-Canales´ sus descubrimientos (los de Lie), no habr´ıa sido posible el nacimiento de la Teor´ıa de la Relatividad” (v´ease [4]). Varias pueden ser las razones de este desconocimiento. Por un lado, no exis- ten en la literatura muchas biograf´ıas sobre este personaje, a pesar de que las escasas existentes sean especialmente muy buenas y completas (v´eanse por ejemplo desde las m´as antiguas [2], [5], [6] y [13], escritas en los primeros a˜nos del siglo XX, a las m´as modernas, [8], [12], [14], [15] y [18], ya en el actual siglo XXI, pasando por las delultimo ´ cuarto del siglo pasado, [1], [3], [7], [9], [16], [17] y [19], de todas las cuales se ha extra´ıdo la mayor parte de las referencias biogr´aficas de este art´ıculo). Porotraparte,laobracient´ıfica de Sophus Lie (Lie,enadelante),apesar de ser muy valorada por muchos cient´ıficos, no deja de ser muy especializada ydif´ıcil de entender a primera vista. Algunos autores han intentado explicar esta circunstancia bas´andose en el hecho de que los art´ıculos originales de Lie estaban escritos en noruego, lo que dificult´o mucho su difusi´on e incluso su co- rrecta traducci´on, o tambi´en en que Lie no usaba el lenguaje anal´ıtico habitual e incluso, ciertamente, porque sus art´ıculos originales no resultaron f´acilmente comprensibles al exceder mucho la intuici´on geom´etrica de Lie aladeotros matem´aticos. De hecho, sus art´ıculos conten´ıan ideas revolucionarias para la ´epoca, desde el punto de vista matem´atico, que no fueron aceptadas por algunos matem´aticos de su tiempo, lo que dificultaba a´un m´as el que ya empezara en aquella ´epoca a ten´ersele en cuenta. El caso es que, como resulta f´acilmente constatable, Lie no est´a suficientemente reconocido en la actualidad como el gran matem´atico que fue (v´ease [20]). Nuestra intenci´on entonces, al escribir este art´ıculo, es la de contribuir, siquiera modestamente, a realzar esta figura. Para ello, y al objeto de que esta pretensi´on llegue al mayor n´umero de personas interesadas, tanto a pro- fesores como a alumnos de cualquier disciplina cient´ıfica, independientemente de su nivel de formaci´on, hemos considerado oportuno dar a conocer la vida yobradeLie vali´endonos de las escasas fotos que se disponen de ´el en la ac- tualidad. Nuestra idea es la de realizar un viaje fotogr´aficoporsuvidaenel que por medio de las fotograf´ıas que se muestran vayamos comentando con un cierto detalle los episodios de la vida de Lie que en ellas se reflejan. Cierta- mente entendemos que este prop´osito puede resultar harto dif´ıcil y que van a ser bastantes los hechos importantes acaecidos en la vida de este matem´atico que no van a verse aqu´ı contemplados, si bien pensamos que al menos esta contribuci´on puede ser un peque˜no paso adelante en el intento de que la figura de Lie llegue a ser m´as reconocida de lo que lo es en la actualidad, y para que este autor vaya alcanzando el reconocimiento que sin duda merece. Comentar finalmente, para terminar esta primera parte de esta Introducci´on que la raz´on principal que nos ha movido a dedicarle este art´ıculo a este matem´atico es la misma que la que ya movi´o a uno de los autores del mis- mo a escribir previamente otros tres art´ıculos publicados por ´el [12, 14, 15]: su Un paseo fotografico´ por la vida de Sophus Lie 57 devoci´on particular por este matem´atico, tras la realizaci´on de su tesis doctoral sobre ´algebras de Lie, que le llev´o primero a bucear en su vida y en su obra, como paso previo al estudio de su teor´ıa. Y esto, junto con la admiraci´on que la figura de Lie tambi´en ha despertado en las otras dos autoras de este trabajo, tras la lectura de una de sus biograf´ıas y el inicio de una primera investigaci´on sobre su obra cient´ıfica. Al objeto de que la lectura de este art´ıculo resulte sencilla y amena para el lector, los autores hemos considerado oportuno estructurarlo en unaunica ´ secci´on, en la que se muestran en orden cronol´ogico las fotograf´ıas que hemos podido conseguir relacionadas con la vida de Lie, que entendemos m´as signi- ficativas, acompa˜nadas de un, en algunos casos breve y en otros m´as extenso, comentario sobre el episodio que reflejan y los personajes que en ellas aparecen. Estas fotograf´ıas se refieren no s´olo al propio Lie,sinotambi´en a todas aquellas personas, familiares o conocidos, objetos y lugares que guardan una estrecha relaci´on con su figura. De todas ellas, las que muestran a los matem´aticos rela- cionados con Lie, han sido tomadas de la excelente p´agina web de biograf´ıas de matem´aticos de la Universidad de Saint Andrews, en Escocia [20]. 1. La vida y obra de Sophus Lie a trav´es de sus fotos Como ya se ha indicado en la Introducci´on, es muy poca la documentaci´on gr´afica de la que se dispone sobre la vida de Sophus Lie, motivada funda- mentalmente por el escaso desarrollo del arte de la fotograf´ıa en los a˜nos en los que esta vida transcurri´o. Pi´ensese que los or´ıgenes de la fotograf´ıa proce- den de la c´amara oscura (del lat´ın camera: habitaci´on o c´amara), que era una habitaci´on cuyaunica ´ fuente de luz era un min´usculo orificio proyectado en una de sus paredes, ya utilizada por Aristoteles´ (384–322 a.C.) para estudiar los eclipses de sol. Posteriormente evolucion´o con el transcurso de los siglos, hasta llegar al siglo XIX, exactamente al a˜no 1816, que es la fecha que para algunos autores constituye el nacimiento de la fotograf´ıa. En ese a˜no, el f´ısico franc´es Joseph Nicephore´ Niepce consigui´o una imagen mediante la utilizaci´on de la c´amara oscura y un procedimiento fotoqu´ımico. M´as tarde, en 1831, el pintor franc´es Louis Jacques Mande´ Daguerre realiz´o fotograf´ıas en planchas re- cubiertas por una capa sensible a la luz de yoduro de plata, y algunos a˜nos m´as tarde, en 1839, el propio Daguerre y el inventor brit´anico William Henry Fox Talbot hicieron p´ublicos sus m´etodos para conseguir fotograf´ıas, sien- do este a˜no de 1839 la fecha que otros autores dan para el nacimiento de la fotograf´ıa. De ah´ı que durante toda la vida de Lie, 1842-1899, este arte de la fotograf´ıa estuviese todav´ıa muy limitado y poco perfeccionado, lo que explica la escasa cantidad de fotos que le hubieran podido tomar y el que, por unas u otras razones,unicamente ´ haya quedado para la posteridad un n´umero m´ınimo de ellas. 58 J. Nu´nez,˜ A. Prieto & V. Sanchez-Canales´ Fotos 1, 2 y 3. La infancia de Lie. En las fotos que mostramos puede verse en una de ellas la situaci´on geogr´afica de Nordfjordeid, y en otra, la aldea en la que naci´o Lie, Eid, en Nordfjordeid, Noruega, el 17 de diciembre de 1842, tomada desde la propia vicar´ıa en la que trabajaba su padre. En la tercera puede verse a Johann Herman Lie,padredeSophus Lie. Johann era un pastor protestante, que estuvo a cargo de la vicar´ıa de la peque˜na aldea de Eid, desde 1836 hasta 1851, en donde la madre de Sophus, Mette Maren (nacida Stabell) era altamente considerada por todos gracias a su trabajo en la granja de la vicar´ıa.
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